The security of information poses challenges for businesses and other organizations that transmit and store information. Data encryption is intended to transform data into a form readable only by authorized users. However a large majority of information is not encrypted due to the difficulty or inconvenience of using most encryption software. In light of this the need has arisen to develop encryption into a “software appliance”. This software knows the identity of the sender and the receiver and the encryption key that is to be used; all it needs from the user is the information which is to be securely transported. By adopting the paradigm of a pre-paid, self addressed express envelope end users will interact with this invention in much the same way they interact with traditional delivery systems that simply provide for the delivery and take place without any further user intervention.